The researchers' findings -- which were presented this week in San Diego, California, at the 105th Annual Meeting of the American Association for Cancer Research -- showed that obesity in male mice altered gene expression in both the dad's sperm and the daughter's breast tissue.
These genetic alterations, passed from father to daughter, lead to higher rates of obesity in female mice pups, as well as increased numbers of "terminal end buds" in their breast tissue -- the site where breast cancer often develops.
"Researchers traditionally study the maternal link to weight and cancer risk. This unusual study demonstrates a potential paternal link as well,” explained the study's lead investigator, Dr. Sonia de Assis, an assistant oncology professor at Georgetown Lombardi. “Until we know about this association in men, we should stick to what we all know is good advice: women -- and men -- should eat a balanced diet not only for their own benefit but also to give their offspring’s the best chances of being healthy."
Both obesity and breast cancer have be significantly influenced by family history, and previous studies have shown overweight moms give birth to larger babies -- children who who may also have a higher risk of breast cancer later in life.
"This study provides evidence that, in animals, a fathers' body weight at the time of conception affects both their daughters' body weight both at birth and in childhood and likely their risk of breast cancer later in life," said de Assis. "Of course, our study was done in mice, but it would be very interesting to know if the same associations hold for daughters of human fathers who were obese at the time of conception."
[Science News Online]